1. Field of the Invention
The present invention relates to a method of setting a processing condition in a photolithography process, an apparatus for setting a processing condition in a photolithography process, a program, and a computer readable recording medium.
2. Description of the Related Art
In a photolithography process in a manufacturing process of a semiconductor device, a plurality of processing and treatments are sequentially performed, for example, resist coating treatment in which a resist film is formed by applying a resist solution onto a wafer surface; exposure processing in which light in a predetermined pattern is applied to the resist film on the wafer to thereby expose the wafer to the light; heat-processing after the exposure which promotes chemical reaction in the resist film (post-exposure baking); developing treatment in which the exposed resist film is selectively dissolved with a developing solution, and so on, so that a predetermined pattern is formed in the resist film on the wafer.
Incidentally, it is necessary to form, on the wafer, the resist pattern with line widths having a uniform predetermined dimension within the wafer. Further, the line width of the resist pattern is greatly affected by processing conditions of, for example, the exposure processing and the heat-processing subsequent thereto in the lithography process. Hence, it has been proposed, as a method of setting the processing conditions in the photolithography process, to measure the line width of the resist pattern formed on the wafer and set the heating temperature in heat-processing after the exposure based on the measurement result (Japanese Patent Application Laid-open No. 2001-143850).
In the aforementioned line width measurement, however, it is necessary to use a so-called electronic CD-SEM (Scanning electron microscope) which measures the line width by applying electron beams to the wafer. In this case, a large quantity of electrons collide against the wafer and may damage, for example, the resist pattern on the wafer. Therefore, the sufficient accuracy of the line width measurement is not secured, causing difficulties to ensure the sufficient accuracy for setting of the heating temperature performed based on the line width measurement. In addition, the line width measurement by the CD-SEM suffers from a disadvantage of consuming much time.
Besides, the result of the line width measurement in the prior art includes a component that is uncontrollable even if the heating temperature after the exposure is adjusted, for example, a component due to the focus at the time of exposure (a focus component). Therefore, there are limitations even if the heating temperature is controlled to thereby make line widths uniform within the wafer based on the result of the line width measurement as in the prior art.